"WE got him!" They were the ecstatic words of MV Orion expedition leader Don McIntyre following the rescue of solo yachtsman Alain Delord in the Southern Ocean.

Mr McIntyre described the dramatic rescue in a post on Facebook, saying tons of water poured in and flooded the lower decks when the crew opened the side gate to get to the Frenchman.

"Trying to shut the door was interesting," he wrote.

"The ship just rolled at the wrong moment... (Captain) Mike repositioned and gave the GO GO... so zodiac launched and when the door opened there was the raft 20m away from me so I immediately changed plans and sent the Zodiac straight for the raft, as the freeboard at the side gate was only 2m to 30cm."

Another crew member grabbed Delord and dragged him into the zodiac.

"I attached the hauling line and we dragged him in through the side of the ship ... then the recovery team grabbed him to take below to the hospital," Mr McIntyre wrote.

"The hospital is now flooded too and we then had to rush to clear the side compartment to close the door again as another wave swamped through... sort of like those submarine stories you see when someone leaves the door open!"

Mr McIntyre said Delord was very tired and a little lethatgic, but otherwise happy and healthy.

"Alain had a weak smile... but Margie and the doctor have him and all looks good," he wrote.

There were plans to move Mr Delord to a guest cabin.

"Amazing... all round," Mr McIntyre wrote.

"Captain Mike did an amazing job getting the ship in a perfect position... the Hercules did a great job dropping smoke flares to mark the way... we only saw him from one mile out and we only had about 30 minutes of light left after it was all done.

Mr Delord had been at sea since last October in his attempt to sail without assistance around the world.

His yacht, Tchouk Tchouk Nougat, was damaged in rough weather off Tasmania on Friday.

After three days adrift on a life raft the 63-year-old was rescued by the cruise ship about 500 nautical miles southwest of Hobart on Sunday night.

The ship was diverted about 1800km to his assistance and had battled deteriorating weather conditions to reach him before sunset, with fears he would have to spend a third night at sea.

The Orion's captain Mike Taylor said at first the vessel's 100 passengers on their once-in-a-lifetime trip to Macquarie Island were "massively disappointed" about being diverted.

"But there was a cheer you could hear right over the ship when we pulled him in through the door," Captain Taylor told ABC radio this morning.

Captain Taylor said the ship was about 680 miles south of Mr Delord when he was contacted by the Rescue Coordination Centre (RCC) in Canberra.

"(The RCC) and called us and said we're Johnny on the spot pretty much," he said.

"It took us a full 53 hours to get from where we were to him."

He said the conditions in which Mr Delord was rescued, with big swells and high winds, were as extreme as he had experienced and that without the help of the RCC the Orion would never have found him.

"It was unbelievable how difficult he was to see," he said.

Mr McIntyre told The Mercury that in the end the rescue took just 25 minutes.

"We changed plans on the run, a lot of things didn't quite work out the way we thought but we modified the plans very quickly," he told The Mercury this morning.

"The zodiac (inflatable boat) went straight to the life raft and we managed to get Alain out very quickly into another raft and came back to the side gate (of the Orion) where we were able to attach a line to him and wait for the swells to work with us and then we quickly hauled him in through the side of the ship.

"He's obviously very weak, very tired ... Basically after a full check out in the hospital the doctor was very surprised at how good a condition he was in."

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